91221266 has 16 divisors (see below), whose sum is σ = 145822464. Its totient is φ = 42698304.

The previous prime is 91221217. The next prime is 91221307. The reversal of 91221266 is 66212219.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18935 + ... + 23258.

It is an arithmetic number, because the mean of its divisors is an integer number (9113904).

Almost surely, 2^91221266 is an apocalyptic number.

91221266 is a deficient number, since it is larger than the sum of its proper divisors (54601198).

91221266 is a wasteful number, since it uses less digits than its factorization.

91221266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42265.

The product of its digits is 2592, while the sum is 29.

The square root of 91221266 is about 9550.9824625533. The cubic root of 91221266 is about 450.1584067833.

The spelling of 91221266 in words is "ninety-one million, two hundred twenty-one thousand, two hundred sixty-six".